The olive tree, the variety of plants, and the moral lesson of cultivation

And you, be as a fruitful olive tree in the house of God, never being stripped of hope, but always keeping the salvation through faith flourishing around you. For in this way you will imitate the evergreen quality of the plant, and you will also rival its abundance of fruit, offering generous almsgiving at every season. But let us return to the investigation of the skilled arrangements. How many kinds of plants sprang up then—some bearing fruit, some for roofing, others suitable for shipbuilding, others for burning? In these again, the arrangement of each tree's parts is varied, and the discovery of each one's particular character is hard to attain, as is the observation of its difference from each of the other kinds. How is it that some of them are deep-rooted and others shallow-rooted, and some grow upright with a single stem, while others are low-growing and immediately divided from the root into many shoots? How is it that those whose branches stretch far out into the air also have deep roots, spreading widely in a circle, as if nature places certain foundations beneath, corresponding to the weight of the things above? How many are the differences of the barks? For some plants are smooth-barked, others cracked-barked; and some of them have a single layer of bark, others many folds. And what is wonderful is that you would find in plants symptoms closely resembling those of human youth and old age. For in the young and flourishing the bark is stretched tight around them, but in those that grow old it becomes wrinkled, as it were, and rough. And some, when cut, sprout again; but others remain without successors, as if enduring the cutting as a kind of death. Indeed, some have observed that pines, when cut down or even burned over, turn into oak forests. And we know that some trees are cured of their natural badness by the care of farmers—for example, the sharp pomegranates and the more bitter almonds, when their trunk near the root is pierced and they receive a greasy wedge of pine driven through the middle of the pith, then change the unpleasantness of their juice into usefulness. Let no one, then, who lives in wickedness despair of himself, knowing that farming changes the qualities of plants, and the care of the soul according to virtue is able to overcome all kinds of infirmities. And the difference in the fruit-bearing of fruit trees is so great that no one could even cover it in speech. For not only are there differences of fruit among the different kinds, but even within the very species of a tree there is much variation; indeed, the growers distinguish one character of fruit for the male trees and another for the female, and they divide even the palms into male and female. And you might at some time see the one they call female letting down her branches, as if in heat, and longing for the embrace of the male; and the tenders of the plants cast into the branches, as it were, certain seeds of the males, the so-called gall-insects, and so she becomes, as it were, aware of the enjoyment, and her branches straighten up again, and her foliage is restored to the proper shape of the plant. They say the same things also about the fig trees.